We're always reporting on urban bike share programs[1] popping up all over the world, but now its time to pick out a few of our favorites that have done especially well in getting people to trade in their four-wheelers for two. From over 300 cities all over the planet, hit the jump for 6 sweet bike sharing schemes that are making a splash and reducing carbon emissions!

Studies of Barcelona’s acclaimed Bicing bike share program[5] have found that the success of their biking scheme has reduced the region’s annual CO2 emissions by 9,000 metric tonnes. Researchers for the British Medical Journal used participants of the program – almost 182,000 of them – and found that the benefits of the bike sharing included reduced greenhouse gas emissions and contributed to 12 less deaths each year due to increased exercise. The study reported that this outweighed the risks and dangers often associated with cycling.

Launched last year, Boston’s bike share[7] was one of a long list of programs which kicked off in 2011. Offered as a green alternative to the existing car sharing initiatives, Boston’s scheme was launched last July with a humble 60 solar-powered stations and 600 bicycles — and the program is still expanding! The city’s mayor, Thomas Menino, announced the program with the hope of moving the city away from its bad cycling reputation. So far the scheme seems to be a hit with a total of 138,000 rides between July and November! The bikes are currently stored away in anticipation of Boston’s harsh winter, but come spring the bicycles you’ll find the bikes all over the city.

Currently the largest bike sharing program in the world, the service in Wuhan, China[9] has announced it will share its program with card holders in Haikou — an ocean city which experiences warm winters that are perfect for cycling. This new idea would enable leisure and business travelers to enjoy bike riding in a tropical climate during the bitter winters of Hangshou. To date, the Hangzhou bike sharing system already has 60,600 bikes — you can find one almost every 100 meters!

Denmark’s beautiful city of Copenhagen has an extraordinary reputation for being a bike friendly city. With large bike paths and a awesome cycling mentality, many residents have several bikes and they’re easy to rent for tourists to enjoy. A city wide plan[11] from RAFFA Archictecture & Design is hoping to increase the population of cyclists even further — from 37% to 50% over the next three years — by implementing a program with a GPS tracking and an online reservation system. The scheme looks quite futuristic and is an innovative plan that could take off around the world.

Following in the footsteps of Paris, bike shares have been huge in London. Launched initially with 15,000 bikes[13] and 1,000 stations, the program aimed to reduce traffic congestion and to clear out some of the city’s smog. Initiated by London’s former Mayor Ken Livingstone, the scheme is now dubbed the “Boris Bikes” under the city’s current Mayor. Distributed across the city the ‘granny bikes’ may look old fashioned, but they are sturdy and act as a natural anti-theft appeal. Paid for with taxes, the scheme is free for riders for the first half an hour and £1 for each hour thereafter.

New York is an awesome place to cycle around and its new bike share program is anticipated bring a whopping 10,000 bikes[15] at 600 stations all over the city, from Brooklyn to Manhattan. The program will provide flexible membership and a 24 hour service to its urban dwellers. Similar to many other bike services, the initial 30 minutes of riding is free, topped off with regular fees for each additional half hour. Sponsoring the program is Alta, and profits will be distributed between the company and the city.